Insulator support



Oct. t

1927' c. CHRISTENSEN INSULATOR SUPPORT Filed Oct. 4. 1920 6mm? m Chfibikemfiem lfizormeys Patented Oct. 4, 1927.

UNITED STATES PATENT oFFTcE.

GHRISTEN CHRISTENSEN, OF .CHIGAGO, ILLINOIS, ASSIGNOR TO ELECTRICAL EN GINEERS EQUIPMENT COMPANY, OF CHICAGO, ILLINOIS, .A. CORPORATION OF ILLI- NOIS.

INSULATOR SUPPORT.

Application filed October 4, 1920. Serial No. 414,388.

My invention relates to improvements in insulators and also to improved forms of clamps for mounting bus bars and similar electrical apparatus.

In the matter of mounting clamps upon insulators, a practically difiicult problem is present. The friable nature of porcelain which material is best suited for the construction of insulators, always has subjected 1 the insulator to the inherent danger of splitting or fracturing due to concentration of stresses at particular points' The unyielding character of porcelain has further been a detriment to the employment of clamps upon insulators. Adding to these difficulties is the lack of uniformity which is unavoidable in the manufacture of insulators, because of the constant expansion and contraction taking place when firing.

As a further object of the invention an improved form of clamp is provided which is adapted to make firm contact with the insulator without concentrated stresses being imparted thereto. In order to compensate for the fragility of the porcelain and to prevent cracking due to the unequalities of the insulator, the clamp is provided with a yielding contact. This permits a multi-pomt contact to be secured and therefore increases the security and rigidity. Furthermore, the clamp is attached in such a'manner as to subject the insulator to stresses only where it is strong.

The particular manner in which I secure the desired results Will be better understood from the following detail description taken in connection with the accompanying drawings, which form part thereof:

Figure 1 is a vertical sectlonal View of one 0 form of insulator having clamps at each end thereof;

. Figure 2 is a to plan View of the same; Fig. 3 isa detail perspective view of one of the clamp sections. Referring to Figures 1 and 2 wherein is illustrated one form of bolt type of insulator clamp, the insulator 1 is of the post type having intermediate corrugations 2, the upper enlarged bead 3 and the lower conical surface 4. The conical surface is formed by providing an enlargement at thisend of the insulator and forming its periphery so that it tapers inwardly and upwardly. The insulators may be provided with recesses of various shapes. The insulator 1 is formed with a recess or bore open at the top, leaving the bottom as a solid base. i i

The lower or bottom part of the insulator is adapted to seat upon any suitable base, indicated at 5, and is held thereto by means of a clamp 6. The clamp 6 comprises an integral circumferential band having a horizontal flange 8 and a circular inclined band 9 which engages the conical seat 4. .The clamp 6 is adapted to be placed over the insulator before the upper clamp is assembled to permit the band 9 to seat and wedge itself into a tight fit as it is drawn into proper position. To the end of drawing the clamp into proper position, a series of bolts 10, in this case four in number, have been provided at a plurality of points about the horizontal flange 8. The bolts 10 may be threaded into the base 5, or may pass thru'a wall or the like. An integral circumferential reinforcing strip; is provided which seats upon the horizontal flange 8 of the clamp 6. At each corner of the strip, or preferably where the bolts 10 are provided for securing the clamp 6 to the" base 5, apertured bosses are formed to permit the bolts 10 to pass therethrough, while the intermediate portions 13 are enlarged or thickened for reinforcement. The circumferential collar serves to prevent buckling of the band 9 when wedged tightly upon its seat- I have purposely not made the band 7 9 and the circumferential collar integral because the purpose of the band 9 is to yield to the irregularities of the insulator and the purpose of the collar is to be rigid and to hold the band firmly by means of the bolts. The clamp 15 for the top of] the insulator. comprises the socket or supporting plate 16 which is provided with threaded'bolt holes 18 intowhich the bolts for mounting the ap-' paratus are threaded. The socket or sup porting plate 16 is preferably flat, on its upper surface to permit proper seating of a fiat member and is provided at its periphery with a plurality of downwardly projecting lugs or ears 17 through whichclamping bolts 19 are passed. Cooperating with the lugs or ears 17' are the ears 20 ofthe sectionalized clamping band 110. This'band 110 is preferably provided in three sections. This provides a three point grip for the clamp, thereby enabling it. to more readily conform its seat to the contour of the bead 3 The sections 21 of the clamping band extend downwardly over the bead 3 having the inner periphery dished so as to provide open pockets for the strips 23; the strips 23 being made of any suitable soft material, such as babbitt or the like. Disposed directly below the lugs 20 of the sections 21 are the lugs 24 through which pass the bolts 25 operating to draw up tightly the lower ends of the sections. The upper ends of the sections are drawn up by the bolts 19. Thus, it is'seen that the sections 21 are not permitted to engage with the bead 3 of the in sulator 1, but instead the strips engage said bead which strips being relatively soft or compressible permit the bolts 19 and 25 to draw up the sections together against the bead without cracking or splitting due to over compression at one or more points.

As clearly illustrated in Fig. l, the inner lugs 24' are disposed within the length of the insulator and the outer lugs 20 are disposed outwardly beyond the end of the insulator so as to detachably secure the plate 16 to the clamp, by means of securing bolts 19' and lugs 17, while holding the plate out of contact with the insulator. It will also be noted that this provides a clamp and plate structure consisting of very few parts so related as to permit the; sections of the: clamp movement independently of the plate to tightly grip the insulator, while also permitting the plate to be removed without the necessity of removing the clamp from the in sulator. This result can be easily accomplished by withdrawing bolts 19 from plate lugs 17', without disturbing bolts 25, as will be readily apparent from Figs. 1 and 2 of the drawings. This feature is of practical value as facilitating application of the clamp and plate to the insulator, as well as permitting quick and easy removal of the plate, when required, without removing the clamp from the insulator.

It will be seen that in addition to a circumferential clamping action by the two sets of bolts 19 and 25, there is a tendency to bend the portion of the clamp between the two sets of bolts and thus lit the clamp more closely to the contour of the head 3. At the same time the shrinking or contracting of this clamp compresses the two sides of the bead 3 so that the top of the insulator is under compression only. As is well known porcelain-is strong in compression but weak in tension.

The plate 16 has sufficient clearance to permit the clamp'to be applied without contacting'with the end of the insulator. Clearance: for bolts or bolt heads may also be provided since end contact is not required and the plate 16 is spaced away from the insulator:

Central coring of the insulator reduces the difficulty of firing and also lessens the having bead about one end, and a periph-,

eral groove adjacent said bead, aclamping member comprising a plurality of segments having one set of apertured bolting lugs within the length of the insulator and an other set of apertured bolting lugs extend ing' beyond the end ofthe insulator, a mounting member spaced from the end of the insulator and having apertured belting lugs adapted for co-operation with the second said apertured lugs of the clamping segments, bolts extending through the first said apertured bolting lugs of the clamping segments for contracting the segments upon the insulator bead, and securing bolts extending through the second said apertured bolting lugs of the through the co-operating mounting member lugs. v

21 In combination, a frangible insulator having a bead peripherally about one end and a peripheral groove adjacent said. bead,

a mounting plate having apertured lugs, a-

clamping member comprising a plurality of segments having apertured bolting lugs within the length of the insulator, said segments extending beyond the adjacent end of the insulator and having other apertured bolting lugs cooperating with the apertured lugs of the mountingplate beyond the end of the insulator, bolts extending through the apertured lugs of the clamping segments within the length of the insulator, and other bolts extending through the apertured segment lugs and cooperating mounting plate lugs beyond the end of the insulator, for contracting the clamping member to bind it upon the peripheral insulator headland to secure the clamping member and mounting plate together. V r

8'. Incombination, a frangible-insulator having a bead peripherally about one end and a peripheral groove adjacent said head, a mounting plate-having apertured lugs, a clamping member comprising a plurality of segments having apertured bolting lugs, within the length of the insulator, said-seg ments extending beyond the adjacent end of the insulator and having apertured bolting lugs co-operating with the apertured lugsof the mounting plate beyond the end of the insulator, bolts extending through the apertured lugs of the clamping'segnients within the length of the'insulator and other; bolts extending through the apertured segment lugs beyondthe end of the insulator and the cooperating mounting plate lugs for con tracting the 1 clamping member to I bind it clamping segments and upon the peripheral insulator bead and to secure the clamping member and mounting plate together, and cushion pad means interposed between the peripheral insulator bead and the clamping member and lying between having inner apertured bolting lugs, said segments extending about and projecting beyond the adjacent end of the insulator and having outer apertured bolting lugs adapted for cooperation with the apertured lugs of the mounting plate beyond the end of the insulator, and securing bolts extending through the inner lugs of the clamping segments and through the outer lugs and the lugs of the plate.

5. In combination, a frangible insulator, a mounting plate having apertured lugs, a clamping member having more than two segments having inner apertured bolting lugs, said segments extending about and projecting beyond the adjacent end of the insulator and having outer apertured bolting lugs cooperating with the apertured lugs of the mounting plate beyond the end of the insulator, bolts extending through the outer lugs of the clamping segments and the lugs of said mounting plate, and bolts extending through the inner lugs 01": the adjacent segments and cooperating with the outer lugs and bolts for tightening said segments about said insulator.

6. In combination, an insulator having a peripheral bead adjacent one end, a clamping member fitting about the insulator and over the bead, said member being sectional and each section being provided with terminal upper and lower lugs disposed respectively on each side of said head, a mounting plate at the end of the insulator having lugs fitting between the upper terminal lugs of the clamp sections, and nut and bolt means passing through said upper and lower lugs for securing the clamp sections together and contracting the clamp about the insulator, the upper bolts of said securing means also passing through the plate lugs and detachably securing the plate to the clamp.

In witness whereof I hereunto subscribe my name this 1st day of October, 1920.

CHRISTEN CHRISTENSEN. 

